This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Human dental plaque is a well-recognized example of a multi-species bacterial community. My research interest lies in the interaction between different bacterial species found in dental plaque and the study of communication between different species of bacteria in the plaque community. This communication includes metabolic interactions between organisms in the biofilm. My current research focus includes studies of communication that occurs between two members of the plaque community, Veillonella atypica and Streptococcus gordonii. When these organisms are growing together, S. gordonii induces expression of an alpha-amylase gene that is not expressed when S. gordonii is grown without V. atypica. My goals are to identify the mechanism of signaling that occurs between these species and determine the importance of amylase expression to development of the mixed-species community. I have recently identified a transcription factor is required for S. gordonii to induce amylase expression in response to V. atypica. I plan to identify other genes required for this signaling.